Our first collaborative project in the field of medicine began in the late 1960's, when we joined neurosurgeons at Boston's Massachusetts General Hospital to develop tiny magnet-tipped catheters for use in blood vessels in the brain, and electromagnets to be positioned near a patient's head to guide these catheters to the site of aneurysms or A-V malformations. Once they were in position, these specialized catheters could then be used to deliver appropriate treatment procedures directly to the afflicted location, without the need to open the skull. The first external guidance magnets were iron-core, water cooled electromagnets, with conical pole tips. A 2 tesla superconducting coil was also built, complete with multi-axis positioning arm and self-contained liquid helium supply.
In collaboration with pediatric surgeons at MGH, we helped develop magnetic bougienage for use in treating esophageal atresia and imperforate anus in infants. This project involved design and manufacture of a water-cooled hollow-conductor electromagnet, in the bore of which the patient was positioned, and construction of stainless steel bougies that the surgeon would place inside the patient as appropriate. Magnetic force exerted on these magnetic bougies resulted in the lengthening of the pouches, or the blind colon, to the extent that surgical repair became feasible.
During the early 1980's, we collaborated with a major pharmaceutical company to develop electromagnet systems for use in capturing drug-carrying magnetic particles in tumors. The particles, manufactured by the company, would be injected into the bloodstream upstream of a target tumor, and then immobilized in the tumor capillary bed by the action of magnetic force generated by an externally-placed electromagnet.